The present invention generally relates to retaining wall blocks and retaining walls constructed from such blocks. More specifically, the present invention relates to a retaining wall block that can be used as whole unit or subdivided into a pair of mating sub-blocks such that the block can be configured to present one of five individual outer faces, thereby permitting the construction of walls having a random natural appearance with varying block face sizes to create the appearance of a natural stone wall.
Retaining walls are used in various landscaping projects and are available in a wide variety of styles. Numerous methods and materials exist for the construction of retaining walls. Such methods include the use of natural stone, poured concrete, precast panels, masonry, and landscape timbers or railroad ties.
In recent years, segmental concrete retaining wall units, which include dry stacked individual blocks, have become widely accepted in the construction of retaining walls. These type of retaining walls are structurally sound, easy and relatively inexpensive to install, and couple the durability of concrete with the attractiveness of various architectural finishes available for the concrete blocks.
Currently, many commercially available blocks are symmetrical and include parallel front and back faces and non-parallel, converging side surfaces. The converging side surfaces allow the blocks to be stacked and form a curvilinear pattern for the retaining wall.
Another important feature of retaining wall blocks is the appearance of the block. One method to make naturally appearing blocks has been described in U.S. Pat. Nos. 5,078,940 and 5,217,630 (both to Sayles). These patents describe a method and apparatus for manufacturing a concrete block having an irregular face surface. The irregular surface can be made to look similar to split stone, and is thus very desirable. The split stone face surface is created by pouring uncured block material into a mold cavity and causing a portion of the material to be retained within the mold as the block is removed from the cavity. The severing of the outer face surface of the block as it is removed from the mold creates the desired appearance without requiring the conventional splitting operation.
Typically, retaining wall blocks are manufactured to have a split face on only the front face of the block. Such blocks do not allow the user the option to use either the front, side or back face of the block interchangeably as the exposed front face.
In addition to utilizing the split face of a block, another highly desirable technique in forming a retaining wall is to create a random, or ashier, pattern along the face of the retaining wall. The random pattern gives the appearance of a mortared or dry-stacked natural stone wall, which is a traditional and well recognized look. The creation of a truly random appearance requires the production of multiple block shapes for use in a single retaining wall. The use of multiple block shapes is inefficient from a production standpoint because this requires multiple molds and additional types of blocks to inventory. If only one face of the block is intended to be the front face, then the block system will suffer a tradeoff between having enough face sizes to create a random, natural appearance and the cost of using multiple molds in creating multiple inventory items.
In addition, when utilizing blocks of various sizes to create a random look on a retaining wall, it is important that the block sizes are multiples of each other such that proper stacking of rows of individual blocks can be carried out to ensure the structural stability of the retaining wall.
Therefore, it would be desirable to produce a retaining wall block having multiple face surfaces that can be used to create a retaining wall having a random shape. Further, it would be desirable to provide a single individual block that can be subdivided into a pair of individual blocks to increase the number of face surfaces without requiring the use of additional molds and creating multiple inventory items. Further, it would be desirable to create a single block having a scoring groove that will allow for splitting of the single block into a pair of mating sub-blocks.
The present invention is a retaining wall block that can be utilized to form a retaining wall having a random appearance. The retaining wall block of the present invention includes a first textured face surface and a second textured face surface that are parallel to each other and spaced apart by the width of the block. Preferably, the length of the first textured face surface is less than the length of the second textured face surface, such that the first and second textured face surfaces can be utilized to create different length face surfaces for the retaining wall.
The retaining wall block further includes a third textured face surface that defines one side of the retaining wall block. The length of the third textured face surface is less than both the first and second textured face surfaces, such that the third textured face surface creates another length face surface for the retaining wall. The textured faces of the retaining wall block can be formed by either hard split or soft split methods.
The retaining wall block includes a scoring groove extending between the first and second textured face surfaces. The scoring groove allows the retaining wall block to be divided into a first sub-block and a second sub-block. When the retaining wall block is divided into the first sub-block and the second sub-block, the first textured face surface is divided into a fourth face surface contained on the first sub-block and a fifth face surface contained on the second sub-block. Likewise, the second face surface is divided into a sixth face surface contained on the first sub-block and a seventh face surface contained on the second sub-block. In accordance with the present invention, the wall block can be configured to define seven distinct face surfaces, six of which have a different length, such that the sub-blocks and the main block can be used to create a random pattern in a retaining wall.
Various other features, objects and advantages of the invention will be made apparent from the following description taken together with the drawings.